Elk Mountain Motor Sports v. UEF, 2012 MT 261 Violation of the express terms of a contract vests the non-breaching party with certain rights.  However, the non-breaching party may waive these rights through its actions or inaction.  Where Petitioner made repeated late payments and the UEF took no steps to refer its claim against Petitioner to collection  until Petitioner rejected an alternative payment arrangement, the UEF accordingly waived its right to terminate the contract based on late payments.